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  <title>Document</title>
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  <script>
    var x = Math.random();
    var y = Math.random();
    console.log(x,y);
     if(x>y){
        console.log(x);
     }
     else{
      console.log(y);
     }
    // var res =x>y?x:y
    // console.log(res);
     function   isRun(today){
     
      today=today.getFullYear()
     
      if( today%4 == 0 && today%100 !=0 ||today%400==0){
      console.log(today+'是闰年');

    }else{
      console.log(today+'不是闰年');
    }return today
    }
     
  
  
    isRun()
  
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